<template>
  <div id="app">
    <transition :name="transitionName">
      <router-view class="router-view" />
    </transition>
    <nav-bar v-if="isShowNav"></nav-bar>
  </div>
</template>

<script>
  import navBar from '@/components/NavBar'
  export default {
    data () {
      return {
        transitionName: 'slide-left',
        isShowNav: true,
        ShowMenuList: ['/', '/home', '/category', '/cart', '/user']
      }
    },
    components: {
      navBar
    },
    watch: {
      $route(to, from) {
        // 有主级到次级
        console.log(this.ShowMenuList)
        if (this.ShowMenuList.includes(to.path)) {
          this.isShowNav = true
        } else {
          this.isShowNav = false
        }
        if (to.meta.index > from.meta.index) {
          this.transitionName = 'slide-left' // 向左滑动
        } else if (to.meta.index < from.meta.index) {
          // 由次级到主级
          this.transitionName = 'slide-right'
        } else {
          this.transitionName = ''   //同级无过渡效果
        }
      }
    }
  }
</script>

<style lang="less">
@import './common/style/mixin';
#app {
  font-family: Avenir, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  color: #2c3e50;
  // height: 100vh;
}

#nav {
  position: absolute;
  top: 0;
  left: 50%;
  z-index: 1000;
}

.router-view{
    width: 100%;
    height: auto;
    position: absolute;
    top: 0;
    bottom: 0;
    margin: 0 auto;
    -webkit-overflow-scrolling: touch;
}

.slide-right-enter-active,
.slide-right-leave-active,
.slide-left-enter-active,
.slide-left-leave-active{
    height: 100%;
    will-change: transform;
    transition: all 500ms;
    position: absolute;
    backface-visibility: hidden;
}
.slide-right-enter{
    opacity: 0;
    transform: translate3d(-100%, 0, 0);
}
.slide-right-leave-active{
    opacity: 0;
    transform: translate3d(100%, 0, 0);
}
.slide-left-enter{
    opacity: 0;
    transform: translate3d(100%, 0, 0);
}
.slide-left-leave-active{
    opacity: 0;
    transform: translate3d(-100%, 0, 0);
}
</style>
